﻿namespace System.Windows.Controls.WpfPropertyGrid.Internal
{
  /// <summary>
  /// Helper class that contains methods that execute mathematical operations
  /// </summary>
  internal static class MathUtil
  {
    /// <summary>
    /// Validates the string passed by parsing it as int and checking if it is inside the bounds specified 
    /// then the resulting int will be incremented/decremented
    /// </summary>
    /// <param name="num">The string to parse as int and increment/decrement</param>
    /// <param name="minValue">The min value for the bound checking</param>
    /// <param name="maxVal">The max value for the bounds checking</param>
    /// <param name="increment">Pass true to increment and false to decrement</param>
    /// <returns>Returns the new number incremented or decremeneted</returns>
    public static int IncrementDecrementNumber(string num, int minValue, int maxVal, bool increment)
    {
      int newNum = ValidateNumber(num, minValue, maxVal);
      newNum = increment ? Math.Min(newNum + 1, maxVal) : Math.Max(newNum - 1, 0);
      return newNum;
    }

    /// <summary>
    /// Parses the number and makes sure that it is within the bounds specified
    /// </summary>
    /// <param name="newNum">The string to parse and validate</param>
    /// <param name="minValue">The min value for the bound checking</param>
    /// <param name="maxValue">The max value for the bound checking</param>
    /// <returns>Returns the int that was constructed from the string + bound checking</returns>
    public static int ValidateNumber(string newNum, int minValue, int maxValue)
    {
      int num;
      if (!int.TryParse(newNum, out num))
        return 0;

      return ValidateNumber(num, minValue, maxValue);
    }

    /// <summary>
    /// makes sure that the number is within the bounds specified
    /// </summary>
    /// <param name="newNum">The number to validate</param>
    /// <param name="minValue">The min value for the bound checking</param>
    /// <param name="maxValue">The max value for the bound checking</param>
    /// <returns>Returns the int that was constructed from the string + bound checking</returns>
    public static int ValidateNumber(int newNum, int minValue, int maxValue)
    {
      newNum = Math.Max(newNum, minValue);
      newNum = Math.Min(newNum, maxValue);

      return newNum;
    }
  }
}
